[Mono-dev] "fixed" as modifier

[Jonathan Pryor]

On Mon, 2006-07-24 at 02:03 +0200, Jakob Petsovits wrote:
> I'm currently writing a C# LL parser for KDevelop, and use the numerous Mono 
> source files as test cases for the parser. I've mainly been following the
> C# specification, and found something in the Mono sources conflicting with it:
> 
> In mcs/tests/gtest-166.cs, there are field declarations where "fixed" is not 
> used as statement, but as modifier for the variable. Quote:
> 
> public unsafe struct TestNew {
>     private fixed char test_1 [128];
>     public fixed bool test2 [4];
> 
>     public fixed int T [2];
>     public fixed bool test20 [4], test21 [40];
> 
>     (...)
> }

...

> Should this be compilable even if it's not specified? Is it a mono bug?
> Can someone tell me more about this?

`fixed' in this context is a Microsoft extension which Mono supports;
see:

	http://msdn2.microsoft.com/en-us/library/zycewsya.aspx
	http://msdn2.microsoft.com/en-us/library/t2yzs44b.aspx
	http://www.mono-project.com/Dllimport#C.23_2.0_Functionality

It allows for simple and efficient fixed-size buffers (the alternatives
are mentioned at
http://www.mono-project.com/Dllimport#Arrays_Embedded_Within_Structures).

I'm not sure why it hasn't been standardized yet.

 - Jon